莺歌海盆地充填史及中—深层储层特征

CHARACTERISTICS OF MEDIUM-DEEP RESERVOIR AND SEDIMENTARY HISTORY IN YINGGEHAI BASIN

王华 朱伟林 王彦

Wang Hua Zhu Weilin Wang Yan

莺歌海盆地为前第三系基底上发育的断坳转换伸展盆地。纵向上总体显示海进充填序列。自始新世以来,该盆地经历了3次由快到慢的沉积过程,T-T(280Ma以前)阶段为快速沉降期,最大总沉降率达600m/Ma,T-T(2.8～5.2Ma)阶段为500m/Ma,T至现今(5.2Ma至现今),最大总沉降率又达600m/Ma.构造作用产生的沉降量占总沉降量的1/2～1/4,其他主要为均衡沉降所致。三角洲砂体、海滩砂体和浊积砂体是本区中-深层主要储集层。黄流组沉积时期,分流河道发育,可能形成良好的储层。

Yinggehai Basin is a fault-depressed basin developed on the basement of PreTertiary System.In vertical,the basin shows generally transgressive filling sequences.The basin underwent three deposition processes since Eocene.T～T(before 28 Ma)was rapid subsidence period,the total rate of descent was 600 m/Ma;the total descent rate of T～T(28 Ma～5.2 Ma)period was 500 m/Ma;that of T～ present day (5.2 Ma～ present) is 600 m/Ma.The amount of subsidence caused by tectonics is about 1/2～1/4 of the total amount;the rest is mainly related to isostatic subsidence.It is proposed that deltaic,beach and turbidite sandbodies are the main mediumdeep reservoirs in the basin;the distributary channel sandbodies deposited during Huangliu Formation may be favourable reservoirs.

10.11743/ogg19990112